Hardness testing method for different inner diameters of stainless steel pipes

Stainless steel pipe is a kind of universal stainless steel, which is widely used to make equipment and parts that require good comprehensive performance (corrosion resistance and formability). In order to maintain the inherent corrosion resistance of stainless steel, steel must contain more than 18% chromium and more than 8% nickel. Stainless steel seamless pipe is a grade of stainless steel produced in accordance with the American ASTM standard.

When the inner diameter of the stainless steel pipe is greater than 26mm, the hardness of the inner wall of the pipe can also be tested with a Rockwell or surface Rockwell hardness tester.

For stainless steel pipes with inner diameter above 6.0mm and wall thickness below 13mm, the W-B75 Webster hardness tester can be used. It is very fast and easy to test and is suitable for quick and non-destructive qualification inspection of stainless steel pipes.

For stainless steel pipes with an inner diameter greater than 30mm and a wall thickness greater than 1.2mm, use Rockwell hardness tester to test HRB and HRC hardness.

For stainless steel pipes with an inner diameter greater than 30mm and a wall thickness less than 1.2mm, the surface Rockwell hardness tester is used to test the hardness of HRT or HRN.

For stainless steel pipes with an inner diameter of less than 0mm and greater than 4.8mm, use a special Rockwell hardness tester for pipes to test the hardness of HR15T.